1. Field of the Invention
This invention relates to a dual-purpose device for sealing the space between a foundation and a sill plate and for providing a physical barrier against termites and other wood boring insects. The device has a portion thereof that adheres to the open face of the sill plate and acts as an impenetrable shield. More particularly, the invention includes a strip of polymeric material that provides sill sealing and precludes weather and insect penetration.
2. Description of the Prior Art
Before the introduction of seismic building codes, residential and small commercial structures were not required to have the sill plate bolted to the concrete foundation. In California, homes built before 1949 were not covered by any specific seismic building code. Upon seismic activity, in buildings which are not bolted to the foundation, the building structure may move on the foundation or even slip off the foundation. Such movement can cause extensive damage to the building and injury to the occupants. Buildings conforming to the seismic building codes have anchor bolts positioned at regular intervals around the perimeter of the foundation wall and extending upward therefrom. The anchor bolts pass through complementary openings in the sill plate and the sill plate is bolted down to the foundation.
Residential construction materials, such as flashings, seals and shields, are frequently revisited to resolve technical problems associated with adjacent materials. A case in point is the galvanic corrosion of aluminum flashings applied over alkaline-copper-quaternary (ACQ) treated woods. Similarly, adhesives having an asphaltic or a bitumen base have been known at ambient temperatures to weep from the installation site and stain adjacent concrete, vinyl or wood. In the cases cited concerns arise as to the life expectancy of the flashing and the aesthetics of the asphaltic-based adhesives. As will be seen herein, other considerations are materials meeting building code standards, utilizing labor-saving installation techniques, and adapting to various changes in the building construction industry.
In the past, residential housing foundations have largely and traditionally been poured concrete or masonry block constructs. To these foundations, wood framing is attached to anchor bolts embedded in the concrete at the top of the poured concrete foundation walls or in the mortar filling the cells of the masonry blocks.
Somewhat more recently an insulated foundation, known as a frost-protected shallow foundation (FPSF), has attracted attention.
An FPSF provides protection against frost damage without the need for excavating below the frost line. An FPSF has insulation placed strategically around the outside of a foundation to direct heat loss from the building toward the foundation, and also to use the earth's natural geothermal energy.
The traditional foundations discussed above are protected from frost-heaving damage by placing the footing below the frost line. Because FPSF are protected from freezing by thermal insulation, bottoms of footings can be just twelve to sixteen inches below grade. This reduces excavation costs, making this an economical alternative for protecting foundations against frost damage. The insulation used in FPSF is commonly rigid expanded or extruded polystyrene foam suitable for below grade application and in compliance with ASTM C 578 Standard. FPSF can be used for both heated and unheated portions of a building.
It is well-known that in buildings constructed with wood in contact with concrete, the wood may be structurally degraded by action of one or more wood pests including, but not limited to termites, ants and other boring insects. In the past, two distinct, but not mutually exclusive, avenues to resolving this problems were followed. First, a chemical barrier utilizing insecticide-treated materials and, secondly, a mechanical barrier such as a metal foil construct.
In the 1990's, Battelle Memorial Institutes did extensive research on long-term insecticide-bearing barriers resulting in patents to Peter Van Voris et al., U.S. Pat. Nos. 6,803,051 and 6,331,308. For purposes of background data, these patents are incorporated herein by reference. These patents describe the binding of a pesticide-carrier mixture into a polymer matrix for long-term protection and provide a comprehensive review of this prior art.
Various construction practices become institutionalized quite rapidly. With this said, it is noted that by the time the Bushberger, infra, application was provisionally filed in 2000, a standard sill plate sealer was described as an elongated strip approximately 0.25 inches thick preferably made from a lightweight polyethylene foam.
In addition to the previously recited art and in preparing for this application, the following patents came to the attention of the inventors and are believed to be relevant to the further discussion of the prior art:
PatentInventorIssue Date6,578,332BushbergerJun. 17, 20036,546,679BushbergerApr. 15, 20036,235,136Kittson et al.May 22, 20015,802,779Hulls et al.Sep. 8, 19985,732,519LeekMar. 31, 19985,091,235VerganosFeb. 25, 19924,528,787Rittinge Jun. 16, 19854,189,877Jentoft et al.Feb. 26, 19803,385,016CromMay 28, 1968
Bushberger—U.S. Pat. No. 6,578,332—issued Jun. 17, 2003
Bushberger in U.S. Pat. No. 6,578,332 describes a foundation seal between the wooden floor deck and the home foundation. The seal is T-shaped with a peel-and-stick adhesive surface on the lower surface of the foundation seal and mounted atop a poured concrete foundation wall.
Bushberger—U.S. Pat. No. 6,546,679—issued Apr. 15, 2003
Here, Bushberger in an earlier patent, provides a foundation protective arrangement utilizing a multi-layer rubberized asphaltic laminate attached to an insulated building foundation.
Rittson et al.—U.S. Pat. No. 6,235,136—issued May 22, 2001
In U.S. Pat. No. 6,235,136, a water-resistant mastic membrane is described. Here the laminate is formed in situ with a fiber glass scrim applied with a resinous adhesive. In the application of materials a final layer of asphalt emulsion is sprayed on the exposed surface.
Hulls et al.—U.S. Pat. No. 5,802,779—issued Sep. 8, 1998
Hulls et al., in their '779 patent, describe a physical barrier to control termites. The barrier is mounted between a foundation and a wooden building structure. The device includes a bait block of cellulosic material which may be inspected to ascertain termite activity, and, if such activity is detected, replaced by a termiticide-laden bait block.
Leek—U.S. Pat. No. 5,732,519—issued Mar. 31, 1998
Leek teaches a one-piece foundation-to-frame connector having an S-shape configuration and, upon installation, is bolted to the concrete foundation and attached to the sill plate or mud sill. The device is primarily designed to retrofit buildings erected prior to those conforming seismic building codes.
Vergano—U.S. Pat. No. 5,091,235—issued Feb. 25, 1992
Vergano '235 describes a sill wrap assembly for providing air infiltration barrier between the sill plate and the foundation wall. The wrap includes a batt of infiltration material laminated into a spun-bonded or woven polyolefin sheet.
Rittinge—U.S. Pat. No. 4,528,787—issued Jul. 16, 1985
The U.S. patent to Rittinge comprises a timber base plate and an additional metal base plate with channels communicating with a cavity.
Jentoft—U.S. Pat. No. 4,189,877—issued Feb. 26, 1980
This shows an earlier mounting on a vinyl strip a reinforcing material, such as a fiber-glass scrim with a foam insulative material bonded thereon. The device is designed for use as an expansion joint cover.
Crom—U.S. Pat. No. 3,385,016—issued May 28, 1968
The Crom patent shows a waterstop-bearing pad which was part of the joint construction between the foundation and the wall of a liquid storage tank.
Various devices for sill sealing and various devices for providing a physical barrier to control termites are shown in the prior art. However, none of the prior art devices provide the combination of features shown hereinbelow in the disclosed device.